The purpose of this study is to determine whether daily use of emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) can prevent HIV infection in men who also receive HIV counseling, condoms, and treatment for other sexually transmitted infections (STIs).

Proportion of missed doses by pill count and by estimate during CASI interview [ Time Frame: At 36 months ] [ Designated as safety issue: No ]

Risk behavior, including number of sexual partners with HIV positive or unknown status, total number of sexual partners, and condom use before, during, and after use of study medication [ Time Frame: At 42 months ] [ Designated as safety issue: Yes ]

High risk for HIV infection including any of the following: 1) No condom use during anal intercourse with a male HIV-positive partner or a male partner of unknown HIV status during the last 6 months; (2) anal intercourse with more than 3 male sex partners during the last 6 months; (3) exchange of money, gifts, shelter, or drugs for anal sex with a male partner during the last 6 months; (4) sex with a male partner and STI diagnosis during the last 6 months or at screening, or (5) sexual partner of an HIV-infected man with whom condoms are not consistently used in the last 6 months.

Able to provide a street address of residence for themselves and one personal contact who would know their whereabouts during the study period

Healthy enough to work, as indicated by score of 80 or greater on the Karnofsky scale

Certain laboratory values

A urine dipstick with a negative or trace result for both glucose and protein within 28 days of enrollment.

Ability to understand and local language for which an informed consent form has been approved by a local IRB and registered with the study sponsor.

Acute HBV infection at the screening visit or presence of treatment indications for hepatitis B based on local practice standards; or clinical signs of hepatic cirrhosis

History of pathological bone fractures not related to trauma

Receiving ongoing therapy with certain HIV/AIDS-related medications or other medications as determined by the investigator

Definitely or possibly received an anti-HIV vaccine while participating in a blinded clinical trial

Current alcohol or drug use that, in the opinion of the investigator, may interfere with the study

Current participation in a clinical trial or cohort study other than sub-studies of this protocol

Any condition at enrollment that, in the opinion of the investigator, would make participation in the study unsafe or would interfere with the study

Sites may utilize additional criteria that restrict enrollment to a subset of people who meet the protocol-defined enrollment criteria.

Exclusion Criteria for Open-Label Extension:

- Site leadership believes participant will have difficulty completing requirements

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00458393